The biotech company Valneva is set to launch a Phase III clinical trial of its single-shot chikungunya vaccine VLA1553 in the first quarter of 2020 after completing Phase II. The company said in a statement that VLA1553 is a single-dose, monovalent, live-attenuated vaccine designed to deliver prophylactic, active immunisation against chikungunya virus (CHIKV) in adults and children aged above one year.
Based on the positive outcomes from its Phase I trial the vaccine secured fast-track designation by the FDA in December 2018, the company said.
The vaccine induced a strong and lasting neutralizing antibody response of more than 300 days comparable to wild-type CHIKV infections, combined with a good safety profile in its pre-clinical studies.
VLA1553 is based on an infectious clone of chikungunya virus named CHIKV LR2006-OPY1 which is attenuated by deleting a major part of the gene encoding the non-structural replicase complex protein nsP3. The genetically engineered virus vaccine is aimed to provide protection against various chikungunya virus outbreak phylogroups and strains.
According to Valneva, the Phase III trial will have a double-blinded, placebo-controlled, multi-centre design and will recruit around 4,000 healthy volunteers. The vaccine is anticipated to be made available by the end of 2022.